The present invention relates to a copying machine with a variable magnification device. More specifically, the present invention relates to a copying machine which can produce a copied image in enlarged or reduced sizes with respect to an original and comprises the paper cassettes mounted in two vertical rows.
A basic configuration of a transfer type electrostatic copying machine which forms an electrostatic latent image on a photoreceptor by exposing the original, develops the electrostatic latent image by a toner and produces a copied image corresponding to the original image by transferring the toner image is commonly known hitherto and has been generally used.
Recently, in order to have various sizes of the original and copied images in different sizes from the original to meet the needs of the customers, the copying magnification is made possible to be selected and the paper feeding are diversified and there is provided the copying machine having the paper cassettes mounted in vertically spaced relation so that they can be selectively pulled off for avoiding troubles of replacing the cassette at every occasion when a different size of the original and/or the magnification are wanted.
In such copying machine, a select key is provided for selecting either of the two paper cassettes mounted in two vertical rows.
Moreover, demands for higher copying speed are strong in recent time and in equal size copying the copying paper is now fed laterally (from a shorter side) to reduce the feeding time which is the main influential factor to affect the copying speed. For variable magnification copying such as when enlarging or reducing the sizes, however, the paper must be fed in proportion to a direction in which the copied image with the variable magnification is formed, that is, the paper is usually fed longitudinally (from a longer side).
Accordingly, even when using the same size paper, the different cassettes have to be used.
In such a configuration, a desired copying may be accomplished without any possibility of miscopying by operating the select key for the paper cassette in accordance with the equal and variable magnification copyings even when using the same paper size. But the operation for selecting the lateral feeding cassette or the longitudinal feeding cassette becomes essential, which is not only troublesome, but, in the worst case, may cause inconveniences such as the miscopying due to the negligence of operation.
Furthermore, there is in the market such a copying machine adapted to select automatically the paper cassette most frequently used as the source of the copying paper in the initial stage after supplying the power to the copying machine or when the machine is not being operated for a fixed period of time. However, it is hardly possible to improve the convenience of operation for use in response to the need of equal and variable magnification copyings, thus the same inconvenience as mentioned above exists.